import java.util.Scanner;

public class Main1565 {
    public static void main(String[] args) {
        Scanner sc=new Scanner(System.in);
        int A=sc.nextInt();
        int B=sc.nextInt();
        int C=sc.nextInt();
        double x=A*0.2+B*0.3+C*0.5;
        System.out.println(String.format("%.0f",x));
    }
}
